Fluoroketone compounds

ABSTRACT

The present invention relates to new fluoroketone compounds from the groups monobromoperfluoroketones, monohydromonobromoperfluoroketones, (perfluoroalkoxy)monobromoperfluoroketones, (fluoroalkoxy)monobromoperfluoroketones, and monochloromonobromoperfluoroketones. These fluoroketone compounds have utility in preventing, controlling and extinguishing fire. These fluoroketone compounds have further utility as additives to reduce or eliminate the flammability of normally flammable working fluids such as refrigerants, foam blowing agents, solvents, aerosol propellants, and sterilants.

CROSS REFERENCE(S) TO RELATED APPLICATION(S)

This application claims the priority benefit of U.S. ProvisionalApplication 60/479,559, filed Jun. 18, 2003.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to new fluoroketone compounds from thegroups monobromoperfluoroketones, monohydromonobromoperfluoroketones,(perfluoroalkoxy)monobromoperfluoroketones,(fluoroalkoxy)monobromoperfluoroketones, andmonochloromonobromoperfluoroketones. These fluoroketone compounds haveutility in preventing, controlling and extinguishing fire.

2. Description of Related Art

Numerous agents and methods of fire fighting are known and can beselected for a particular fire, depending upon factors such as its size,location and the type of combustible materials involved. Halogenatedhydrocarbon fire fighting agents have traditionally been utilized inflooding applications protecting fixed enclosures (e.g., computer rooms,storage vaults, telecommunications switching gear rooms, libraries,document archives, petroleum pipeline pumping stations, and the like),or in streaming applications requiring rapid extinguishing (e.g.,military aircraft, commercial hand-held extinguishers). Suchextinguishing agents are not only effective but, unlike water, alsofunction as “clean extinguishing agents,” causing little, if any, damageto the enclosure or its contents.

The most commonly-used halogenated hydrocarbon extinguishing agents havebeen the bromine-containing compounds bromotrifluoromethane (CF₃Br,Halon™1301) and bromochlorodifluoromethane (CF₂ClBr, Halon™1211). Thesebromine-containing halocarbons are highly effective in extinguishingfires and can be dispensed either from portable streaming equipment orfrom an automatic room flooding system activated either manually or bysome method of fire detection. However, these compounds have been linkedto ozone depletion. The Montreal Protocol and its attendant amendmentshave mandated that Halon™1211 and 1301 production be discontinued.

Thus, there is a need in this field for substitutes or replacements forthe commonly-used, bromine-containing fire extinguishing agents. Suchsubstitutes should have a low ozone depletion potential; should have theability to extinguish, control, and prevent fires, e.g., Class A (trash,wood, or paper), Class B (flammable liquids or greases), and/or Class C(electrical equipment) fires; and should be “clean extinguishingagents,” i.e., be electrically non-conducting, volatile or gaseous, andleave no residue upon use. Preferably, substitutes will also be low intoxicity, not form flammable mixtures in air, have acceptable thermaland chemical stability for use in extinguishing applications, and haveshort atmospheric lifetimes and low global warming potentials.

Various different fluorinated hydrocarbons have been suggested for useas fire fighting agents. For example, in U.S. Pat. No. 6,300,378,Tapscott discloses tropodegradeable bromine-containing halocarbonadditives to decrease the flammability of refrigerants, foam blowingagents, solvents, aerosol propellants, and sterilants. In U.S. Pat. No.6,478,979, Rivers et al. disclose the use of perfluorinated ketones infire extinguishing.

BRIEF SUMMARY OF THE INVENTION

The aforementioned objectives of substitutes or replacements for thecommonly-used, bromine-containing fire extinguishing agents are met bythe present invention which comprises monobromoperfluoroketones,monohydromonobromoperfluoroketones,(perfluoroalkoxy)monobromoperfluoroketones,(fluoroalkoxy)monobromoperfluoroketones, andmonochloromonobromoperfluoroketones having utility in fighting fire.

DETAILED DESCRIPTION OF THE INVENTION

Monobromoperfluoroketones CF₃C(O)CF₂CF₂CBrF₂, CF₃CF₂C(O)CF₂CF₂CBrF₂ andCF₃C(O)CF₂CF₂CF₂CF₂CBrF₂ of the present invention may be prepared bybromination of the corresponding monohydroperfluoroketones by thetechnique of Kolenko and Plashkin in Izvestiya Akademii Nauk SSSR,Seriya Khimicheskaya, pages 1648 to 1650 (1977), and by Zapevalov, etal. in Zhumal Organicheskoi Khimii, Vol. 26, pages 265 to 272 (1990).CF₃C(O)CF₂CF₂CBrF₂ may be prepared by bromination ofmonohydroperfluoroketone CF₃C(O)CF₂CF₂CHF₂, which may be prepared byisomerization of an epoxide as described by Zapelov et al. in ZhumalVsesoyuznogo Khimicheskogo Obshchestva im. D. I. Mendeleeva, Vol. 18,pages 591 to 593 (1973). CF₃CF₂C(O)CF₂CF₂CBrF₂ andCF₃C(O)CF₂CF₂CF₂CF₂CBrF₂ may be prepared by bromination ofmonohydroperfluoroketones CF₃CF₂C(O)CF₂CF₂CHF₂ andCF₃C(O)CF₂CF₂CF₂CF₂CHF₂, respectively, by the technique of Saloutina, etal. in Zhumal Organicheskoi Khimii, Vol. 29, pages 1325 to 1336 (1993).

Preparation of monobromoperfluoroketones CF₃C(O)CF₂CF₂CBrF₂,CF₃CF₂C(O)CF₂CF₂CBrF₂ and CF₃C(O)CF₂CF₂CF₂CF₂CBrF₂ of the presentinvention by conversion of the monohydroperfluoroketone terminal C—Hbond to a terminal C—Br may be carried out using brominating agents suchas elemental bromine, phosphorous pentabromide, or a mixture of bromineand phosphorous tribromide. The preferred brominating agent is a mixtureof bromine and phosphorous tribromide.

Reaction of a monohydroperfluoroketone and a brominating agent may becarried out under substantially anhydrous conditions in the vapor phaseor liquid phase in a container fabricated from materials of constructionsuitable for contact with bromine and hydrogen bromide at temperaturesof about 300° C. to 600° C. Examples of such materials of constructioninclude metallic alloys containing a nickel such as, for example,Hastelloy™ C and Hastelloy™ B. The reaction takes place under theautogenous pressures of the reactants at the reaction temperature.

The ratio of the brominating agent to the monohydroperfluoroketones isat least about 1 mole of brominating agent per mole ofmonohydroperfluoroketone and preferably about 1.3 moles of brominatingagent per mole of monohydroperfluoroketone. More than 1.7 moles ofbrominating agent per mole of monohydroperfluoroketone provides littlebenefit.

Brominating the monohydroperfluoroketone may be conducted attemperatures of from about 300° C. to about 600° C. Using the preferredbrominating agent, the temperature is preferably conducted from about300° C. to 350° C. Contact times between the brominating agent and themonohydroperfluoroketone may be from about one hour to about twentyhours.

At the end of the contact period the reaction mixture is cooled and thentreated with a reagent to decompose the brominating agent such as sodiumsulfite. The monobromoperfluoroketone may be isolated by collecting theorganic phase followed by distillation.

Monobromoperfluoroketones CF₃CF₂C(O)CBrFCF₂CF₃, CF₃CF₂CBrFC(O)CF(CF₃)₂,(CF₃)₂CBrC(O)CF(CF₃)₂, CF₃CF₂C(O)CBr(CF₃)CF₂CF₃ andCF₃CBrFC(O)CF(CF₃)CF₂CF₃, as well as mixtures ofmonobromoperfluoroketones of the present invention CF₃C(O)CBrFCF₂CF₃ andCF₃CBrFC(O)CF₂CF₃, or CF₃C(O)CBrFCF₂CF₂CF₂CF₃ andCF₃CBrFC(O)CF₂CF₂CF₂CF₃, or CF₃CF₂C(O)CBrFCF₂CF₂CF₃ andCF₃CF₂CBrFC(O)CF₂CF₂CF₃, may be prepared by reacting perfluoroolefinepoxides, such as the epoxide of perfluoro-2-pentene,perfluoro-2-heptene, or perfluoro-3-heptene, with an alkali metalbromide as described by Saloutina et al. in Izvestiya Akademii NaukSSSR, Seriya Khimicheskaya, pages 1893 to 1896 (1982). Theperfluoroolefin epoxides may be prepared by reaction of theperfluoroolefin with an alkali metal hypohalite as described by Kolenko,et al. in Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, pages2509-2512 (1979).

The reaction of perfluoroolefin epoxides with alkali metal bromides maybe carried out in a polar non-protic solvent such as glycol ethers suchas ethylene glycol dimethyl ether, diethylene glycol dimethyl ether,triethylene glycol dimethyl ether, and tetraethylene glycol dimethylether, N,N-dimethyl formamide, N,N-dimethyl acetamide, dimethylsulfolane, dimethylsulfoxide, N-methylpyrrolidinone, and alkane nitrilessuch as acetonitrile, propionitrile, and butyronitrile. Preferredsolvents for contacting perfluoroolefin epoxides with alkali metalbromides are glycol ethers such as ethylene glycol dimethyl ether,diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, andtetraethylene glycol dimethyl ether, and alkane nitriles such asacetonitrile, propionitrile, and butyronitrile.

Alkali metal bromides suitable for opening the perfluoroolefin epoxidering and formation of a C—Br bond include lithium bromide, sodiumbromide, potassium bromide, and cesium bromide; sodium and lithiumbromide are preferred.

The mole ratio of the alkali metal bromide to the perfluoroolefinepoxide is at least about 2:1, preferably about 10:1.

Reaction of alkali metal bromides and perfluoolefin epoxide may beconducted in the liquid phase under substantially anhydrous conditionsat temperatures of from about 10° C. to about 150° C., with contacttimes of from about 0.5 hour to about thirty-six hours. The pressureunder which the reaction occurs is not critical.

At the end of the contact period the reaction mixture may be distilledto isolate the monobromoperfluoroketone.

Monobromoperfluoroketones of the present invention CBrF₂C(O)CF(CF₃)₂,CBrF₂CF₂C(O)CF₂CF₃, CF₃CBrFCF₂C(O)CF(CF₃)₂, CF₃CF₂C(O)CF₂CF₂CF₂CBrF₂,CBrF₂CF₂CF₂C(O)CF(CF₃)₂, and CBrF₂CF₂C(O)CF(CF₃)CF₂CF₃ may be preparedby reacting a monobromoperfluoroacyl fluoride with a perfluoroolefin.

CBrF₂C(O)CF(CF₃)₂ may be prepared by reacting CBrF₂C(O)F with CF₃CF═CF₂;CBrF₂CF₂C(O)CF₂CF₃ may be prepared by reacting CBrF₂CF₂C(O)F withCF₂═CF₂; CF₃CF₂C(O)CF₂CF₂CF₂CBrF₂ may be prepared by reactingCBrF₂CF₂CF₂CF₂C(O)F with CF₂═CF₂; CBrF₂CF₂CF₂C(O)CF(CF₃)₂ may beprepared by reacting CBrF₂CF₂CF₂C(O)F with CF₃CF═CF₂;CBrF₂CF₂C(O)CF(CF₃)CF₂CF₃ may be prepared by reacting CBrF₂CF₂C(O)F withCF₃CF═CFCF₃; and CF₃CBrFCF₂C(O)CF(CF₃)₂ may be prepared by reactingCF₃CBrFCF₂C(O)F with CF₃CF═CF₂.

Monobromoperfluoroketones of the present invention CF₃C(O)CBr(CF₃)₂,CF₃CBrFC(O)CF₂CF₂CF₃, CF₃C(O)CBr(CF₃)CF₂CF₃, CF₃C(O)CF(CF₃)CBrFCF₃,CF₃CF₂CF₂C(O)CBr(CF₃)₂, may be prepared by reacting a perfluoroacylfluoride with a monobromoperfluoroolefin.

CF₃C(O)CBr(CF₃)₂ may be prepared by reacting CF₃C(O)F with CF₃CBr═CF₂;CF₃CBrFC(O)CF₂CF₂CF₃ may be prepared by reacting CBrF═CF₂ withCF₃CF₂CF₂C(O)F; a mixture of CF₃C(O)CBr(CF₃)CF₂CF₃ andCF₃C(O)CF(CF₃)CBrFCF₃ may be prepared by reacting CF₃CBr═CFCF₃ withCF₃C(O)F; and CF₃CF₂CF₂C(O)CBr(CF₃)₂ may be prepared by reactingCF₃CF₂CF₂C(O)F with CF₃CBr═CF_(2.)

(Perfluoroalkoxy)monobromoperfluoroketones of the present invention areof the formula R¹C(O)CF(CF₃)OR^(F), wherein R¹ is a C₁ to C₃monobromoperfluoroalkyl radical, and R^(F) is a C₁ to C₃ perfluoroalkylradical, may be obtained by reacting monobromoperfluoroacyl fluorides ofthe formula R¹C(O)F with perfluorovinyl ethers of the formula CF₂═CFORF.Representative (perfluoroalkoxy)monobromoperfluoroketones of the presentinvention include CBrF₂C(O)CF(CF₃)OCF₃, CBrF₂CF₂C(O)CF(CF₃)OCF₃,CBrF₂CF₂CF₂C(O)CF(CF₃)OCF₃, CBrF₂C(O)CF(CF₃)OC₂F₅,CBrF₂CF₂C(O)CF(CF₃)OC₂F₅, CBrF₂C(O)CF(CF₃)OCF₂C₂F₅,CBrF₂CF₂C(O)CF(CF₃)OCF₂C₂F₅, CBrF₂C(O)CF(CF₃)OCF(CF₃)₂,CBrF₂CF₂C(O)CF(CF₃)OCF(CF₃)₂, CF₃CBrFC(O)CF(CF₃)OCF(CF₃)₂,CF₃CBrFC(O)CF(CF₃)OCF₃, and CF₃CBrFC(O)CF(CF₃)OC₂F₅.

CBrF₂C(O)CF(CF₃)OCF₃ may be prepared by reacting CBrF₂C(O)F withCF₂═CFOCF₃; CBrF₂CF₂C(O)CF(CF₃)OCF₃ may be prepared by reactingCBrF₂CF₂C(O)F with CF₂═CFOCF₃; CBrF₂CF₂CF₂C(O)CF(CF₃)OCF₃ may beprepared by reacting CBrF₂CF₂CF₂C(O)F with CF₂═CFOCF₃;CBrF₂C(O)CF(CF₃)OC₂F₅ may be prepared by reacting CBrF₂C(O)F withCF₂═CFOC₂F₅; CBrF₂CF₂C(O)CF(CF₃)OC₂F₅ may be prepared by reactingCBrF₂CF₂C(O)F with CF₂═CFOC₂F₅; CBrF₂C(O)CF(CF₃)OCF₂C₂F₅ may be preparedby reacting CBrF₂C(O)F with CF₂═CFOCF₂C₂F₅; CBrF₂CF₂C(O)CF(CF₃)OCF₂C₂F₅may be prepared by reacting CBrF₂CF₂C(O)F with CF₂═CFOCF₂C₂F₅;CBrF₂C(O)CF(CF₃)OCF(CF₃)₂ may be prepared by reacting CBrF₂C(O)F withCF₂═CFOCF(CF₃)₂; CBrF₂CF₂C(O)CF(CF₃)OCF(CF₃)₂ may be prepared byreacting CBrF₂CF₂C(O)F with CF₂═CFOCF(CF₃)₂; CF₃CBrFC(O)CF(CF₃)OCF₃ maybe prepared by reacting CF₃CBrFC(O)F with CF₂═CFOCF₃; andCF₃CBrFC(O)CF(CF₃)OC₂F₅ may be prepared by reacting CF₃CBrFC(O)F withCF₂═CFOC₂F₅.

(Perfluoroalkoxy)monobromoperfluoroketones of the formulaR¹C(O)CF(CF₃)OR^(F) may also be obtained by reactingperfluoroalkoxyperfluoroacyl fluorides of the formula R^(F)OCF(CF₃)C(O)Fwith a monobromoperfluoroolefin. Representative(perfluoroalkoxy)monobromoperfluoroketones of the present inventioninclude CF₃CBrFC(O)CF(CF₃)OCF₃, (CF₃)₂CBrC(O)CF(CF₃)OCF₃,CF₃CBrFC(O)CF(CF₃)OC₂F₅, (CF₃)₂CBrC(O)CF(CF₃)OC₂F₅,CF₃CBrFC(O)CF(CF₃)OCF₂C₂F₅, and CF₃CBrFC(O)CF(CF₃)OCF(CF₃)₂.

CF₃CBrFC(O)CF(CF₃)OCF₃ may be prepared by reacting CF₃OC(CF₃)FC(O)F withCF₂═CBrF; (CF₃)₂CBrC(O)CF(CF₃)OCF₃ may be prepared by reactingCF₃OC(CF₃)FC(O)F with CF₃CBr═CF₂; CF₃CBrFC(O)CF(CF₃)OC₂F₅ may beprepared by reacting C₂F₅OC(CF₃)FC(O)F with CF₂═CBrF;(CF₃)₂CBrC(O)CF(CF₃)OC₂F₅ may be prepared by reacting C₂F₅OC(CF₃)FC(O)Fwith CF₃CBr═CF₂; CF₃CBrFC(O)CF(CF₃)OCF₂C₂F₅ may be prepared by reactingC₂F₅CF₂OC(CF₃)FC(O)F with CF₂═CBrF; and CF₃CBrFC(O)CF(CF₃)OCF(CF₃)₂ maybe prepared by reacting (CF₃)₂CFOC(CF₃)FC(O)F with CF₂═CBrF.

(Fluoroalkoxy)monobromoperfluoroketones of the present invention are ofthe formula R¹C(O)CX(CF₃)OR², wherein X is H or F, R¹ is a C₁, C₂, or C₃bromoperfluoroalkyl radical, and R² is a C, to C₃ alkyl or fluoroalkylradical, may be prepared by reacting monobromoperfluoroacyl fluorides ofthe formula R¹C(O)F with hydrofluorovinyl ethers of the formulaCF₂═CXOR². Representative (fluoroalkoxy)monobromoperfluoroketonesinclude CBrF₂C(O)CF(OCF₂CHF₂)CF₃, CBrF₂C(O)CH(OCF₂CHF₂)CF₃,CBrF₂C(O)CF(OCH₃)CF₃, and CBrF₂C(O)CF(CF₂OCH₃)CF₃.

CBrF₂C(O)CF(OCF₂CHF₂)CF₃ may be prepared by reacting CBrF₂C(O)F withCF₂═CFOCF₂CHF₂; CBrF₂C(O)CH(OCF₂CHF₂)CF₃ may be prepared by reactingCBrF₂C(O)F with CF₂═CHOCF₂CHF₂; and CBrF₂C(O)CF(OCH₃)CF₃ may be preparedby reacting CBrF₂C(O)F with CF₂═CFOCH₃.

Another (fluoroalkoxy)monobromoperfluoroketone of the present inventionincludes CBrF₂C(O)CF(CF₂OCH₃)CF₃, prepared by reacting CBrF₂C(O)F withCF₃CF═CFOCH₃.

The reaction of fluoroacyl fluorides with fluoroolefins is described byFawcett, et al. in U.S. Pat. No. 3,185,734 and Journal of the AmericanChemical Society, Vol. 84, pages 4285 to 4288 (1962). The teachings ofthese references may be applied to the aforementioned preparation ofmonobromoperfluoroketones by the reaction of monobromoperfluoroacylfluorides with perfluoroolefins as well as the aforementionedpreparation of monobromoperfluoroketones by the reaction ofperfluoroacyl fluorides with monobromoperfluoroolefins. The teachings ofthese references may also be applied to the preparation of(perfluoroalkoxy)monobromoperfluoroketones by the reaction ofmonobromoperfluoroacyl fluorides with perfluorovinyl ethers, or by thereaction of perfluoroalkoxyperfluoroacyl fluorides withmonobromoperfluoroolefins. The teachings of these references may also beapplied to the preparation of (fluoroalkoxy)monobromoperfluoroketones bythe reaction of monobromoperfluoroacyl fluorides with hydrofluorovinylethers.

Though not essential for preparing the ketones of the present invention,reaction of a fluoroacyl fluoride (such as a perfluoroacyl fluoride ormonobromoperfluoroacyl fluoride) with a fluoroolefin (such as aperfluoroolefin, monobromoperfluoroolefin, perfluorovinyl ether orhydrofluorovinyl ether) may be performed in a polar non-protic solventsuch as N,N-dimethyl formamide, N,N-dimethyl acetamide, dimethylsulfolane, dimethylsulfoxide, N-methylpyrrolidinone, and glycol etherssuch as ethylene glycol dimethyl ether, diethylene glycol dimethylether, triethylene glycol dimethyl ether, and tetraethylene glycoldimethyl ether. Preferred solvents for reacting fluoroacyl fluorideswith fluoroolefin are glycol ethers. The reaction may be run undersubstantially anhydrous conditions.

The mole ratio of the fluoroolefin to fluoroacyl fluoride during thereaction may be at least about 1:1 to about 2:1, and preferably is about1.1. More than about 2 moles of fluoroolefin per mole of fluoroacylfluoride provides little benefit.

The reaction of fluoroacyl fluoride with fluoroolefin is preferablyconducted in the presence of a fluoride ion source such as an alkalimetal fluoride, alkali metal hydrogen difluoride (i.e., a bifluoride),alkali-earth metal fluoride, tetraalkylammonium fluoride,tetraalkylammonium hydrogen fluoride, trialkylammonium fluoride, ornon-oxidizing transition metal fluorides. Preferred fluoride ion sourcesare potassium fluoride, cesium fluoride, and potassium bifluoride. Thefluoride ion source may be present at a level of 5 mole percent to 20mole percent, preferably about 10 mole percent, based on the quantity offluoroolefin present.

Temperatures of from about 50° C. to about 250° C., preferably fromabout 100° C. to about 150° C. are effective to produce any of thefluorinated ketones of the present invention by reaction of a fluoroacylfluoride with a fluoroolefin.

The reaction of fluoroacyl fluoride with fluoroolefin may take place inbatch mode or in semi-batch mode with the fluoroacyl fluoride addedgradually to the mixture of the fluoroolefin, solvent, and fluoride ionsource. Contact times suitable for the reaction may be from about 0.5hour to about 24 hours. The reaction typically takes place underautogenous pressure provided by the reactants at the reactiontemperature.

Though not added intentionally to the reactions, hydrogen fluoride maybe present in small amounts during the reactions of fluoroacyl fluoridesdue to the presence of traces of water. Reaction of fluoroacyl fluorideswith fluoroolefins may be conducted in a vessel formed of materialscompatible with hydrogen fluoride at elevated temperatures andpressures. Examples of such materials include stainless steels, inparticular of the austenitic type, the well-known high nickel alloys,such as Monel™ nickel-copper alloys, Hastelloy™ nickel-based alloys and,Inconel™ nickel-chromium alloys, and copper-clad steel.

The fluoroketone products may be isolated from the reaction mixture as alower liquid layer or by distillation. After removing traces of fluoridesalts by washing with water, such products may be purified bydistillation.

The present invention further includesmonohydromonobromoperfluoroketones in which one of the C—F bonds in aperfluoroketone has been replaced by a C—Br bond, and in addition,another of the C—F bonds in said perfluoroketone has been replaced by aC—H bond. Monohydromonobromoperfluoroketones of the present inventioncomprise CHF₂CF₂C(O)CBrFCF₃, (CF₃)₂CHC(O)CBrFCF₃, CHF₂CF₂C(O)CBr(CF₃)₂,(CF₃)₂CHC(O)CBr(CF₃)₂, (CF₃)₂CHC(O)CBrF₂ and CBrF₂CF₂C(O)CH(CF₃)₂.

CHF₂CF₂C(O)CBrFCF₃ may be prepared by reacting CHF₂CF₂C(O)F withCBrF═CF₂; (CF₃)₂CHC(O)CBrFCF₃ may be prepared by reacting (CF₃)₂CHC(O)Fwith CBrF═CF₂; CHF₂CF₂C(O)CBr(CF₃)₂ may be prepared by reactingCHF₂CF₂C(O)F with CF₃CBr═CF₂; (CF₃)₂CHC(O)CBr(CF₃)₂ may be prepared byreacting (CF₃)₂CHC(O)F with CF₃CBr═CF₂; and CBrF₂CF₂C(O)CH(CF₃)₂ may beprepared by reacting CBrF₂CF₂C(O)F with CF₃CH═CF₂. Themonohydromonobromoperfluoroketone (CF₃)₂CHC(O)CBrF₂ may be prepared bythe reaction of the bromofluoroacyl fluoride CBrF₂C(O)F with themonohydroperfluoroolefin CF₃CH═CF₂.

The production of monohydromonobromoperfluoroketones by the reaction ofmonohydroperfluoroacyl fluorides with monobromoperfluoroolefins, as wellas by the reaction of monobromoperfluoroacyl fluorides withmonohydroperfluoroolefins, may use reaction conditions and proceduresimilar to those discussed hereinabove for the reaction of a fluoroacylfluoride with a fluoroolefin.

The present invention further comprisesmonochloromonobromoperfluoroketones in which one of the C—F bonds in aperfluoroketone has been replaced by a C—Br bond, and in addition,another one of the C—F bonds in said perfluoroketone has been replacedby a C—Cl bond. Monochloromonobromoperfluoroketones of the presentinvention comprise compounds of the formula CXF₂CFYC(O)CFRCF₃, wherein Xis Cl and Y is Br, or wherein X is Br and Y is Cl, and wherein R is F, aCF₃ radical, or a C₂F₅ radical. These compounds may be prepared bycontacting an acid fluoride of the formula CXF₂CFYC(O)F, prepared asdisclosed by Darst, et al. in U.S. Pat. No. 5,557,010, with aperfluoroolefin of the formula CFR═CFR. Representativemonochloromonobromoperfluoroketones include CClF₂CFBrC(O)CF₂CF₃,prepared by reacting CClF₂CFBrC(O)F with CF₂═CF₂; CBrF₂CClFC(O)CF₂CF₃,prepared by reacting CBrF₂CClFC(O)F with CF₂═CF₂; CClF₂CFBrC(O)CF(CF₃)₂,prepared by reacting CClF₂CFBrC(O)F with CF₂═CFCF₃; andCBrF₂CClFC(O)CF(CF₃)₂, prepared by reacting CBrF₂CClFC(O)F withCF₂═CFCF₃.

Monochloromonobromoperfluoroketones of the present invention furthercomprise CClF₂C(O)CBr(CF₃)₂, CClF₂CF₂C(O)CBr(CF₃)₂,CF₃CClFC(O)CBr(CF₃)₂, CClF₂C(O)CBrFCF₃, CClF₂CF₂C(O)CBrFCF₃, andCF₃CClFC(O)CBrFCF₃ which may be prepared by reacting amonochloroperfluoroacyl fluoride with a monobromoperfluoroolefin.

CClF₂C(O)CBr(CF₃)₂ may be prepared by reacting CClF₂C(O)F withCF₃CBr═CF₂; CClF₂CF₂C(O)CBr(CF₃)₂ may be prepared by reactingCClF₂CF₂C(O)F with CF₃CBr═CF₂; CF₃CClFC(O)CBr(CF₃)₂ may be prepared byreacting CF₃CClFC(O)F with CF₃CBr═CF₂; CClF₂C(O)CBrFCF₃ may be preparedby reacting CClF₂C(O)F with CF₂═CBrF; CClF₂CF₂C(O)CBrFCF₃ may beprepared by reacting CClF₂CF₂(O)F with CF₂═CBrF; CF₃CClFC(O)CBrFCF₃ maybe prepared by reacting CF₃CClFC(O)F with CF₂═CBrF.

Monochloromonobromoperfluoroketones of the present invention furtherinclude CBrF₂C(O)CCl(CF₃)₂, CBrF₂CF₂C(O)CCl(CF₃)₂, CBrF₂C(O)CClFCF₃, andCBrF₂CF₂C(O)CClFCF₃ which may be prepared by reacting amonobromoperfluoroacyl fluoride with a monochloroperfluoroolefin.

CBrF₂C(O)CCl(CF₃)₂ may be prepared by reacting CBrF₂C(O)F withCF₃CCl═CF₂; CBrF₂CF₂C(O)CCl(CF₃)₂ may be prepared by reactingCBrF₂CF₂C(O)F with CF₃CCl═CF₂; CBrF₂C(O)CClFCF₃ may be prepared byreacting CBrF₂C(O)F with CF₂═CClF; and CBrF₂CF₂C(O)CClFCF₃ may beprepared by reacting CBrF₂CF₂C(O)F with CF₂═CClF.

The formation of monohydromonobromoperfluoroketones by the reaction offluoroacyl fluorides of the formula CXF₂CFYC(O)F with perfluoroolefins,or by the reaction of monochloroperfluoroacyl fluorides withmonobromoperfluoroolefins, or by the reaction of monobromoperfluoroacylfluorides with monochloroperfluoroolefins, may use reaction conditionsand procedure similar to those discussed hereinabove for the reaction ofa fluoroacyl fluoride with a fluoroolefin.

Fluoroketones of the present invention comprise the previously definedmonobromoperfluoroketones, (perfluoroalkoxy)monobromoperfluoroketones,(fluoroalkoxy)monobromoperfluoroketones,monohydromonobromoperfluoroketones, andmonochloromonobromoperfluoroketones, and have utility in fire fightingas fire preventing, controlling and extinguishing agents.

The present fluoroketones may be utilized alone, in combination with oneanother, or in combination with a co-fire-fighting agent or propellantselected from known fire fighting agents of the classeshydrofluorocarbons, hydrochlorofluorocarbons, perfluorocarbons,perfluoroketones, perfluoropolyethers, hydrofluoropolyethers,hydrofluoroethers, chlorofluorocarbons, bromofluorocarbons,bromochlorofluorocarbons, hydrobromocarbons, iodofluorocarbons, andhydrobromofluorocarbons. Such co-agents can be chosen to enhance thefire fighting capabilities or modify the physical properties (e.g.,modify the rate of introduction by serving as a propellant) of a firefighting composition for a particular type (or size or location) of firehazard and can preferably be utilized in ratios (of co-agent tofluoroketone) such that the resulting composition does not formflammable mixtures in air. Such fire fighting mixtures may contain fromabout 10-90% by weight of at least one fluoroketone and from about90-10% by weight of at least one co-agent.

Of particular utility are azeotropic and azeotrope-like mixturescontaining the present fluoroketones and one or more compounds selectedfrom the group consisting of perfluoroketones and hydrofluorocarbons.Such mixtures may provide a fire fighting composition with a lowerboiling point than either constituent of the mixture as well as providea constant ratio of the components of the mixture during discharge.

The present fluoroketones may be solids, liquids, or gases under ambientconditions, but are preferably utilized for fire preventing, controllingand extinguishing in either the liquid or the gaseous state (or both).Thus, normally solid compounds are preferably utilized aftertransformation to liquid and/or gas through melting, sublimation, ordissolution in a liquid co-agent. Such transformation can occur uponexposure of the compound to the heat of a fire.

Introduction of a fire controlling or extinguishing composition cangenerally be carried out by releasing the composition into an enclosedarea surrounding a fire. Any of the known methods of introduction can beutilized provided that appropriate quantities of the composition aremetered into the enclosed area at appropriate intervals. For example, acomposition can be introduced by streaming, e.g., using conventionalportable (or fixed) fire extinguishing equipment; by misting; or byflooding, e.g., by releasing (using appropriate piping, valves, andcontrols) the composition into an enclosed area surrounding a fire. Thecomposition can optionally be combined with an inert propellant, e.g.,nitrogen, argon, decomposition products of glycidyl azide polymers orcarbon dioxide, to increase the rate of discharge of the compositionfrom the streaming or flooding equipment utilized. When the compositionis to be introduced by streaming or local application, fluoroketoneshaving normal boiling points in the range of from about 40° C. to about130° C. (especially fluoroketones that are liquid under ambientconditions) are preferably utilized. When the composition is to beintroduced by misting, fluoroketones having boiling points in the rangeof from about 40° C. to about 110° C. are generally preferred. And, whenthe composition is to be introduced by flooding, fluoroketones havingboiling points in the range of from about 40° C. to about 80° C. aregenerally preferred.

Preferably, the extinguishing composition is introduced to a fire orflame in an amount sufficient to extinguish the fire or flame. Oneskilled in this field will recognize that the amount of extinguishingcomposition needed to extinguish a particular fire will depend upon thenature and extent of the hazard. When the extinguishing composition isto be introduced by flooding, cup burner test data is useful indetermining the amount or concentration of extinguishing compositionrequired to extinguish a particular type and size of fire. The amount offluoroketone used to control or extinguish fire is generally an averageresulting concentration of between about 1 and about 10 percent by gasvolume of fluoroketone.

The present fluoroketones are also useful for preventing a combustiblematerial from igniting. The present fluoroketones thus also have utilityin preventing fires or deflagration in an air-containing, enclosed areathat contains combustible materials of the self-sustaining ornon-self-sustaining type. Such a utility involves a process comprisingthe step of introducing into an air-containing, enclosed area anon-flammable fire preventing composition that is essentially gaseousthat comprises at least one present fluoroketone, the composition beingintroduced and maintained in an amount sufficient to prevent combustionof combustible materials in the enclosed area.

For fire prevention, fluoroketones (and any co-agent(s) utilized) can bechosen so as to provide a composition that is essentially gaseous underuse conditions. Preferred compound(s) have boiling points in the rangeof from about 40° C. to about 130° C. The fluoroketone composition isintroduced and maintained in an amount sufficient to prevent combustionof combustible materials in the enclosed area. The amount varies withthe combustibility of the particular flammable materials present in theenclosed area. Combustibility varies according to chemical compositionand according to physical properties such as surface area relative tovolume, porosity, etc. The present fluoroketones can be used toeliminate the combustion-sustaining properties of air and to therebyprevent the combustion of flammable materials (e.g., paper, cloth, wood,flammable liquids, and plastic items). The present fluoroketones can bemaintained continuously if a threat of fire is always present or can beintroduced into an atmosphere as an emergency measure if a threat offire or deflagration develops.

Fluoroketones of the present invention have further utility as additivesto reduce or eliminate the flammability of normally flammable workingfluids, for example, refrigerants, foam blowing agents, solvents,aerosol propellants, and sterilants. The present fluoroketones have thecharacteristics of high effectiveness for flammability reduction, buthave short atmospheric lifetimes (on the order of days or weeks)resulting in low ozone depletion potentials and global warmingpotentials.

The amount of fluoroketone needed will depend on the application, thematerial whose flammability is to be reduced, and the specificfluoroketone. The fluoroketones will be most useful at concentrationsranging from 1-80% by weight, although the concentration of fluoroketonein the mixtures can range from 0.1-99% by weight. Expedient proportionsinclude 540% by weight of fluoroketone for refrigerant mixtures, 5-50%by weight of fluoroketone for foam blowing agent mixtures, 1-99%fluoroketone for solvent mixtures, 5-25% by weight fluoroketone foraerosol propellant mixtures, and 5-40% by weight fluoroketone forsterilant mixtures.

Refrigerants, foam blowing agents, solvents, aerosol propellants, and/orsterilants may be either gases (vapors) or liquids. In many cases,materials are stored in one form and used in another. For example, foamblowing agents may be stored as a liquid and used as a gas when the foamis actually blown. In some cases, both gaseous and liquid forms arepresent during use. Thus, refrigerants are present in both vapor andliquid forms during the operation of most refrigerators or heat pumps.In the gas phase, normally flammable refrigerants, foam blowing agents,solvents, aerosol propellants, and/or sterilants containing theflammability reducing fluoroketone will have a reduced flammability dueto the presence of the fluoroketone. Of particular importance is theaction of the fluoroketone when the refrigerant, foam blowing agent,solvent, aerosol propellant, and/or sterilant is in the liquid state.The present fluoroketones are volatile, though some are more-so and someless-so. Thus, normally flammable liquid refrigerants, foam blowingagents, solvents, aerosol propellants, and sterilants containing thesefluoroketones will, upon full or partial evaporation, produce vaporsthat have lower flammabilities due to the presence of the flammabilityreducing fluoroketones, which also evaporate. Of particular importanceis that release of the fluoroketones when refrigerants, foam blowingagents, solvents, aerosol propellants, and refrigerants evaporate or areotherwise released into an area will aid in reducing flammability of thevapor above the liquid/vapor interface (i.e., combustible liquids) andexplosivity of the vapor if released into a volume such as a room.

The present fluoroketones find utility in a method for reducing oreliminating the flammability of solvent used in metal, electronic, andprecision cleaning and/or degreasing, and/or used for dissolution of asolute, said method comprising the steps of:

-   -   a) providing at least one fluoroketone of the present invention,        and    -   b) mixing said fluoroketone with said solvent, wherein said        solvent comprises at one component selected from the group of        hydrocarbons, halocarbons, hydrochlorofluorocarbons,        hydrofluorocarbons, terpenes, siloxanes, alcohols, ketones,        esters, ethers, hydrofluoroethers, monochlorotoluenes,        benzotrifluoride, and hydrofluoropolyethers to form a mixture        containing between about 0.1 and about 99 percent by weight of        said fluoroketone.

EXAMPLES Example 1 Synthesis of CF₃CBrFC(O)C₂F₅ and CF₃C(O)CBrFC₂F₅

Preparation of Perfluoro2,3-epoxypentane

A 2 L creased flask was equipped with a mechanical stirrer, athermocouple well, an addition funnel, and a dry ice distillation headconnected to a calcium sulfate drying tube. The flask was charged with800 mL of sodium hypochlorite solution (10-13% chlorine) and 15.0 g oftetrabutylammonium hydrogen sulfate. The addition funnel was chargedwith 60.0 g (0.24 mole) of cold perfluoro-2-pentene. The solution wascooled to 20° C. using an ice-water bath and the mixture stirred at 600rpm. The F-2-pentene was then added to the sodium hypochlorite solutionover the course of about one hour while maintaining the temperature ofthe reaction in the range of 20-22° C. After the addition was complete,the mixture was stirred for an additional hour. The flask was then setfor distillation and the epoxide product (32.8 g, CAS Reg. No.[71917-15-2]) was then distilled out of the mixture by raising the pottemperature to about 40° C.

Preparation of a Mixture of Perfluoro-2-bromo-3-pentanone andPerfluoro-3-bromo-2-pentanone

A one liter flask was equipped with a mechanical stirrer, a thermocouplewell, and a dry ice condenser connected to a Drierite™ tube. The flaskwas charged with 146.3 g (1.42 moles) of sodium bromide, 10 g (0.031mole) of tetrabutyl ammonium bromide, and 235.8 g (300 mL) ofacetonitrile. The mixture was stirred for 15 minutes at room temperatureand then cooled to about 6° C. using an ice-water bath. A 32.9 g (0.12mole) sample of perfluoro2,3-epoxypentane, prepared as described above,was then added to the flask in one portion. The ice bath was removed andthe reaction was stirred rapidly for six hours at room temperature.

The flask was then set for vacuum distillation. Thebromoperfluoropentanone mixture (50.3 g) was then distilled out of theflask at a pressure of about 80 mm Hg and a pot temperature about 20-25°C. Analysis of the distillate by gas chromography-mass spectroscopyindicated it was primarily an azeotropic mixture of acetonitrile (31.1GC area %), perfluoro-2-bromo-3-pentanone (13.6%), andperfluoro-3-bromo-2-pentanone (47.0%).

The distillate was subjected to flash chromatography on silica gel usingoctane as an eluant. The column effluent containing primarily octane andthe mixture of perfluoro-2-bromo-3-pentanone andperfluoro-3-bromo-2-pentanone was then subjected to two vacuumdistillations at a pressure of 56 and 100 torr, respectively, toseparate the bromoperfluoroketones from the bulk of the octane. Thelow-boiling fractions from the vacuum distillations were thenre-distilled at atmospheric pressure. The fractions collected at a headtemperature of 71.2-72.8° C. were combined. The product was a mixture ofperfluoro-2-bromo-3-pentanone and perfluoro-3-bromo-2-pentanone in molarratio of 1.0 to 1.12 with overall purity of >98 GC area %.

Example 2 Fire Extinguishing Concentration of a Mixture ofCF₃CBrFC(O)C₂F₅, and CF₃C(O)CBrFC₂F₅

The fire extinguishing concentration of a mixture of CF₃CBrFC(O)C₂F₅ andF₃C(O)CBrFC₂F₅, in a 1.0 to 1.12 mole ratio respectively, was determinedby the ICI Cup Burner method. This method is described in “Measurementof Flame-Extinguishing Concentrations” R. Hirst and K. Booth, FireTechnology, vol. 13(4): 296-315 (1977).

Specifically, an air stream is passed at 40 liters/minute through anouter chimney (8.5 cm. I. D. by 53 cm. tall) from a glass beaddistributor at its base. A fuel cup burner (3.1 cm. O.D. and 2.15 cm.I.D.) is positioned within the chimney at 30.5 cm. below the top edge ofthe chimney. The fire extinguishing agent is added to the air streamprior to its entry into the glass bead distributor while the air flowrate is maintained at 40 liters/minute for all tests. The air and agentflow rates are measured using calibrated rotameters.

The test is conducted by adjusting the fuel (n-heptane) level in thereservoir to bring the liquid fuel level in the cup burner just evenwith the ground glass lip on the burner cup. With the air flow ratemaintained at 40 liters/minute, the fuel in the cup burner is ignited.The fire extinguishing agent is added in measured increments until theflame is extinguished.

The fire extinguishing concentration is determined from the followingequation: Extinguishing concentration=(F₁/(F₁+F₂))×100, where F₁ is theagent flow rate and F₂ is the air flow rate. TABLE 1 FIRE EXTINGUISHINGCONCENTRATION FIRE EXTINGUISHING AGENT (volume % in air) EXAMPLECF₃CBrFC(O)C₂F₅ and 3.5 F₃C(O)CBrFC₂F₅ in a 1.0 to 1.12 mole ratiomixture, respectively COMPARATIVE CF₃CHFCF₃ (HFC-227ea) 7.3 CF₃CHFCHF₂(HFC-236ea) 10.2 CF₃CF₂CH₂Cl (HCFC-235cb) 6.2 CF₄ 20.5 C₂F₆ 8.7 CF₃Br(Halon-1301) 4.2 CF₂ClBr (Halon 1211) 6.2 CHF₂Cl 13.6

1. A compound selected from the group consisting of: CF₃C(O)CBrFCF₂CF₃,CF₃C(O)CF₂CF₂CBrF₂, CBrF₂C(O)CF(CF₃)₂, CF₃C(O)CBr(CF₃)₂,CBrF₂CF₂C(O)CF₂CF₃, CF₃CBrFC(O)CF₂CF₃, CF₃CBrFC(O)CF₂CF₂CF₃,CF₃CF₂C(O)CBrFCF₂CF₃, CF₃CF₂C(O)CF₂CF₂CBrF₂, CF₃C(O)CBr(CF₃)CF₂CF₃,CF₃C(O)CF(CF₃)CBrFCF₃, CF₃C(O)CBrFCF₂CF₂CF₂CF₃,CF₃C(O)CF₂CF₂CF₂CF₂CBrF₂, CF₃CBrFC(O)CF₂CF₂CF₂CF₃,CF₃CF₂C(O)CBrFCF₂CF₂CF₃, CF₃CF₂C(O)CF₂CF₂CF₂CBrF₂,CF₃CF₂CBrFC(O)CF₂CF₂CF₃, CBrF₂CF₂C(O)CF(CF₃)CF₂CF₃,CF₃CBrFC(O)CF(CF₃)CF₂CF₃, CF₃CF₂C(O)CBr(CF₃)CF₂CF₃,CF₃CF₂C(O)CF(CBrF₂)CF₂CF₃, CBrF₂CF₂CF₂C(O)CF(CF₃)₂,CF₃CF₂CBrFC(O)CF(CF₃)₂, CF₃CF₂CF₂C(O)CBr(CF₃)₂, (CF₃)₂CBrC(O)CF(CF₃)₂,CF₃CBrFCF₂C(O)CF(CF₃)₂, CHF₂CF₂C(O)CBr(CF₃)₂, (CF₃)₂CHC(O)CBr(CF₃)₂,CHF₂CF₂C(O)CBrFCF₃, (CF₃)₂CHC(O)CBrFCF₃, (CF₃)₂CHC(O)CBrF₂,CBrF₂CF₂C(O)CH(CF₃)₂, CBrF₂C(O)CF(CF₃)OCF₃, CBrF₂CF₂C(O)CF(CF₃)OCF₃,CBrF₂CF₂CF₂C(O)CF(CF₃)OCF₃, CBrF₂C(O)CF(CF₃)OC₂F₅,CBrF₂CF₂C(O)CF(CF₃)OC₂F₅, CBrF₂C(O)CF(CF₃)OCF₂C₂F₅,CBrF₂CF₂C(O)CF(CF₃)OCF₂C₂F₅, CBrF₂C(O)CF(CF₃)OCF(CF₃)₂,CBrF₂CF₂C(O)CF(CF₃)OCF(CF₃)₂, CF₃CBrFC(O)CF(CF₃)OCF(CF₃)₂,CF₃CBrFC(O)CF(CF₃)OCF₃, CF₃CBrFC(O)CF(CF₃)OC₂F₅, CF₃CBrFC(O)CF(CF₃)OCF₃,(CF₃)₂CBrC(O)CF(CF₃)OCF₃, CF₃CBrFC(O)CF(CF₃)OC₂F₅,(CF₃)₂CBrC(O)CF(CF₃)OC₂F₅, CF₃CBrFC(O)CF(CF₃)OCF₂C₂F₅,CF₃CBrFC(O)CF(CF₃)OCF(CF₃)₂, CBrF₂C(O)CF(OCF₂CH F₂)CF₃,CBrF₂C(O)CH(OCF₂CHF₂)CF₃, CBrF₂C(O)CF(OCH₃)CF₃, CBrF₂C(O)CF(CF₂OCH₃)CF₃,CClF₂CFBrC(O)CF₂CF₃, CBrF₂CFClC(O)CF₂CF₃, CClF₂CFBrC(O)CF(CF₃)₂,CBrF₂CFClC(O)CF(CF₃)₂, CClF₂CFBrC(O)CF(CF₃)(C₂F₅),CBrF₂CFClC(O)CF(CF₃)(C₂F₅), CClF₂C(O)CBr(CF₃)₂, CClF₂CF₂C(O)CBr(CF₃)₂,CF₃CClFC(O)CBr(CF₃)₂, CClF₂C(O)CBrFCF₃, CClF₂CF₂(O)CCBrFCF₃,CF₃CClFC(O)CBrFCF₃, CBrF₂C(O)CCl(CF₃)₂, CBrF₂CF₂C(O)CCl(CF₃)₂,CBrF₂C(O)CClFCF₃ and CBrF₂CF₂C(O)CClFCF₃.
 2. A monobromoperfluoroketoneselected from the group consisting of: CF₃C(O)CBrFCF₂CF₃,CF₃C(O)CF₂CF₂CBrF₂, CBrF₂C(O)CF(CF₃)₂, CF₃C(O)CBr(CF₃)₂,CBrF₂CF₂C(O)CF₂CF₃, CF₃CBrFC(O)CF₂CF₃, CF₃CBrFC(O)CF₂CF₂CF₃,CF₃CF₂C(O)CBrFCF₂CF₃, CF₃CF₂C(O)CF₂CF₂CBrF₂, CF₃C(O)CBr(CF₃)CF₂CF₃,CF₃C(O)CF(CF₃)CBrFCF₃, CF₃C(O)CBrFCF₂CF₂CF₂CF₃,CF₃C(O)CF₂CF₂CF₂CF₂CBrF₂, CF₃CBrFC(O)CF₂CF₂CF₂CF₃,CF₃CF₂C(O)CBrFCF₂CF₂CF₃, CF₃CF₂C(O)CF₂CF₂CF₂CBrF₂,CF₃CF₂CBrFC(O)CF₂CF₂CF₃, CBrF₂CF₂C(O)CF(CF₃)CF₂CF₃,CF₃CBrFC(O)CF(CF₃)CF₂CF₃, CF₃CF₂C(O)CBr(CF₃)CF₂CF₃,CF₃CF₂C(O)CF(CBrF₂)CF₂CF₃, CBrF₂CF₂CF₂C(O)CF(CF₃)₂,CF₃CF₂CBrFC(O)CF(CF₃)₂, C F₃CF₂CF₂C(O)CBr(CF₃)₂, (CF₃)₂CBrC(O)CF(CF₃)₂and CF₃CBrFCF₂C(O)CF(CF₃)₂.
 3. A monohydromonobromoperfluoroketoneselected from the group consisting of: CH F₂CF₂C(O)CBr(CF₃)₂,(CF₃)₂CHC(O)CBr(CF₃)₂ CHF₂CF₂C(O)CBrFCF₃, (CF₃)₂CHC(O)CBrFCF₃,(CF₃)₂CHC(O)CBrF₂ and CBrF₂CF₂C(O)CH(CF₃)₂.
 4. A(perfluoroalkoxy)monobromoperfluoroketone of the formulaR¹C(O)CF(CF₃)OR^(F), wherein R¹ is a C₁ to C₃ monobromoperfluoroalkylradical, and R^(F) is a C₁ to C₃ perfluoroalkyl radical.
 5. The(perfluoroalkoxy)monobromoperfluoroketone of claim 4 selected from thegroup consisting of: CBrF₂C(O)CF(CF₃)OCF₃, CBrF₂CF₂C(O)CF(CF₃)OCF₃,CBrF₂CF₂CF₂C(O)CF(CF₃)OCF₃, CBrF₂C(O)CF(CF₃)OC₂F₅,CBrF₂CF₂C(O)CF(CF₃)OC₂F₅, CBrF₂C(O)CF(CF₃)OCF₂C₂F₅,CBrF₂CF₂C(O)CF(CF₃)OCF₂C₂F₅, CBrF₂C(O)CF(CF₃)OCF(CF₃)₂,CBrF₂CF₂C(O)CF(CF₃)OCF(CF₃)₂, CF₃CBrFC(O)CF(CF₃)OCF(CF₃)₂,CF₃CBrFC(O)CF(CF₃)OCF₃, CF₃CBrFC(O)CF(CF₃)OC₂F₅, CF₃CBrFC(O)CF(CF₃)OCF₃,(CF₃)₂CBrC(O)CF(CF₃)OCF₃, CF₃CBrFC(O)CF(CF₃)OC₂F₅,(CF₃)₂CBrC(O)CF(CF₃)OC₂F₅, CF₃CBrFC(O)CF(CF₃)OCF₂C₂F₅, andCF₃CBrFC(O)CF(CF₃)OCF(CF₃)₂.
 6. A (fluoroalkoxy)monobromoperfluoroketoneof the formula R¹C(O)CX(CF₃)OR², wherein X is H or F, R¹ is a C¹, C₂, orC₃ bromoperfluoroalkyl radical, and R² is a C, to C₃ alkyl orfluoroalkyl radical.
 7. The (fluoroalkoxy)monobromoperfluoroketone ofclaim 6 selected from the group consisting of: CBrF₂C(O)CF(OCF₂CHF₂)CF₃,CBrF₂C(O)CH(OCF₂CHF₂)CF₃, CBrF₂C(O)CF(OCH₃)CF₃, andCBrF₂C(O)CF(CF₂OCH₃)CF₃.
 8. A monochloromonobromoperfluoroketoneselected from the group consisting of: CClF₂CFBrC(O)CF₂CF₃,CBrF₂CFClC(O)CF₂CF₃, CClF₂CFBrC(O)CF(CF₃)₂, CBrF₂CFClC(O)CF(CF₃)₂,CClF₂CFBrC(O)CF(CF₃)(C₂F₅), CBrF₂CFClC(O)CF(CF₃)(C₂F₅),CClF₂C(O)CBr(CF₃)₂, CClF₂CF₂C(O)CBr(CF₃)₂, CF₃CClFC(O)CBr(CF₃)₂,CClF₂C(O)CBrFCF₃, CClF₂CF₂C(O)CBrFCF₃, CF₃CClFC(O)CBrFCF₃,CBrF₂C(O)CCl(CF₃)₂, CBrF₂CF₂C(O)CCl(CF₃)₂, CBrF₂C(O)CClFCF₃, andCBrF₂CF₂C(O)CClFCF₃.
 9. A compound of claim 1 which isCF₃C(O)CBrFCF₂CF₃.
 10. A compound of claim 1 which isCF₃C(O)CF₂CF₂CBrF₂.
 11. A compound of claim 1 which isCBrF₂C(O)CF(CF₃)₂.
 12. A compound of claim 1 which is CF₃C(O)CBr(CF₃)₂.13. A compound of claim 1 which is CBrF₂CF₂C(O)CF₂CF₃.
 14. A compound ofclaim 1 which is CF₃CBrFC(O)CF₂CF₃.
 15. A compound of claim 1 which isCF₃CBrFC(O)CF₂CF₂CF₃.
 16. A compound of claim 1 which isCF₃CF₂C(O)CBrFCF₂CF₃.
 17. A compound of claim 1 which isCF₃CF₂C(O)CF₂CF₂CBrF₂.
 18. A compound of claim 1 which isCF₃C(O)CBr(CF₃)CF₂CF₃.
 19. A compound of claim 1 which isCF₃C(O)CF(CF₃)CBrFCF₃.
 20. A compound of claim 1 which isCF₃C(O)CBrFCF₂CF₂CF₂CF₃.
 21. A compound of claim 1 which isCF₃C(O)CF₂CF₂CF₂CF₂CBrF₂.
 22. A compound of claim 1 which isCF₃CBrFC(O)CF₂CF₂CF₂CF₃.
 23. A compound of claim 1 which isCF₃CF₂C(O)CBrFCF₂CF₂CF₃.
 24. A compound of claim 1 which isCF₃CF₂C(O)CF₂CF₂CF₂CBrF₂.
 25. A compound of claim 1 which isCF₃CF₂CBrFC(O)CF₂CF₂CF₃.
 26. A compound of claim 1 which isCBrF₂CF₂C(O)CF(CF₃)CF₂CF₃.
 27. A compound of claim 1 which isCF₃CBrFC(O)CF(CF₃)CF₂CF₃.
 28. A compound of claim 1 which isCF₃CF₂C(O)CF(CBrF₂)CF₂CF₃.
 29. A compound of claim 1 which isCBrF₂CF₂CF₂C(O)CF(CF₃)₂.
 30. A compound of claim 1 which isCF₃CF₂CBrFC(O)CF(CF₃)₂.
 31. A compound of claim 1 which isCF₃CF₂CF₂C(O)CBr(CF₃)₂.
 32. A compound of claim 1 which is(CF₃)₂CBrC(O)CF(CF₃)₂.
 33. A compound of claim 1 which isCHF₂CF₂C(O)CBr(CF₃)₂.
 34. A compound of claim 1 which is(CF₃)₂CHC(O)CBr(CF₃)₂.
 35. A compound of claim 1 which isCHF₂CF₂C(O)CBrFCF₃.
 36. A compound of claim 1 which is(CF₃)₂CHC(O)CBrFCF₃.
 37. A compound of claim 1 which is(CF₃)₂CHC(O)CBrF₂.
 38. A compound of claim 1 which isCBrF₂C(O)CF(CF₃)OCF₃.
 39. A compound of claim 1 which isCBrF₂CF₂C(O)CF(CF₃)OCF₃.
 40. A compound of claim 1 which isCBrF₂CF₂CF₂C(O)CF(CF₃)OCF₃.
 41. A compound of claim 1 which isCBrF₂C(O)CF(CF₃)OC₂F₅.
 42. A compound of claim 1 which isCBrF₂CF₂C(O)CF(CF₃)OC₂F₅.
 43. A compound of claim 1 which isCBrF₂C(O)CF(CF₃)OCF₂C₂F₅.
 44. A compound of claim 1 which isCBrF₂CF₂C(O)CF(CF₃)OCF₂C₂F₅.
 45. A compound of claim 1 which isCBrF₂C(O)CF(CF₃)OCF(CF₃)₂.
 46. A compound of claim 1 which isCBrF₂CF₂C(O)CF(CF₃)OCF(CF₃)₂.
 47. A compound of claim 1 which isCF₃CBrFC(O)CF(CF₃)OCF(CF₃)₂.
 48. A compound of claim 1 which isCBrF₂C(O)CF(OCF₂CHF₂)CF₃.
 49. A compound of claim 1 which isCBrF₂C(O)CH(OCF₂CHF₂)CF₃.
 50. A compound of claim 1 which isCBrF₂C(O)CF(OCH₃)CF₃.
 51. A compound of claim 1 which isCBrF₂C(O)CF(CF₂OCH₃)CF₃.
 52. A compound of claim 1 which isCClF₂CFBrC(O)CF₂CF₃.
 53. A compound of claim 1 which isCBrF₂CFClC(O)CF₂CF₃.
 54. A compound of claim 1 which isCClF₂CFBrC(O)CF(CF₃)₂.
 55. A compound of claim 1 which isCBrF₂CFClC(O)CF(CF₃)₂.
 56. A compound of claim 1 which isCClF₂CFBrC(O)CF(CF₃)(C₂F₅).
 57. A compound of claim 1 which isCBrF₂CFClC(O)CF(CF₃)(C₂F₅).
 58. A compound of claim 1 which isCClF₂C(O)CBr(CF₃)₂.
 59. A compound of claim 1 which isCClF₂CF₂C(O)CBr(CF₃)₂.
 60. A compound of claim 1 which isCF₃CClFC(O)CBr(CF₃)₂.
 61. A compound of claim 1 which isCClF₂C(O)CBrFCF₃.
 62. A compound of claim 1 which isCClF₂CF₂C(O)CBrFCF₃.
 63. A compound of claim 1 which isCF₃CClFC(O)CBrFCF₃.
 64. A compound of claim 1 which isCBrF₂C(O)CCl(CF₃)₂.
 65. A compound of claim 1 which isCBrF₂CF₂C(O)CCl(CF₃)₂.
 66. A compound of claim 1 which isCBrF₂C(O)CClFCF₃.
 67. A compound of claim 1 which isCBrF₂CF₂C(O)CClFCF₃.
 68. A compound of claim 1 which isCF₃CBrFC(O)CF(CF₃)OCF₃.
 69. A compound of claim 1 which isCF₃CBrFC(O)CF(CF₃)OC₂F₅.
 70. A compound of claim 1 which isCF₃CBrFC(O)CF(CF₃)OCF₃.
 71. A compound of claim 1 which is(CF₃)₂CBrC(O)CF(CF₃)OCF₃.
 72. A compound of claim 1 which isCF₃CBrFC(O)CF(CF₃)OC₂F₅.
 73. A compound of claim 1 which is(CF₃)₂CBrC(O)CF(CF₃)OC₂F₅.
 74. A compound of claim 1 which isCF₃CBrFC(O)CF(CF₃)OCF₂C₂F₅.
 75. A compound of claim 1 which isCF₃CBrFC(O)CF(CF₃)OCF(CF₃)₂.
 76. A compound of claim 1 which isCF₃CBrFCF₂C(O)CF(CF₃)₂.
 77. A compound of claim 1 which isCBrF₂CF₂C(O)CH(CF₃)₂.